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["3.890\"","Bare","boresizeheads:3.890\"","Cathedral Port","cylinder heads","intakeheads:LS1","LS"]
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Factory Mast LS1 - Cathedral - Gen III & IV Cylinder Heads
Factory Mast LS1 - Cathedral - Gen III & IV Cylinder Heads
243/799/317 Factory Ported Cylinder Heads
Priced Per Pair of Heads - allow minimum 4 weeks for shipping
No Core
Factory Mast ported GM cathedral porting service is a great option for those looking for great bang for your buck. These ports are now available to you in our Factory Mast cylinder heads.
Specifications: GM Stock LS Cathedral
Stock Chamber (65cc)
Intake Port Volume 223 cc
Exhaust Port Volume 83 cc
CNC porting
Seats: Stock Iron
Guides: CHE Bronze Guides 8mm Stock Valve
Minimum Bore: 3.890"
All Factory Mast Heads get:
Teardown | Clean | Inspect
5-Axis CNC Porting
Precision CNC Valve Job
Recondition/clean all gasket surfaces and ends
Hand Blending
Surfacing
Final Wash and Assembly
Pressure Tested
Flow:
Intake
0.100 - 66 cfm
0.200 - 141cfm
0.300 - 209 cfm
0.400 - 257 cfm
0.500 - 295 cfm
0.600 - 305 cfm
0.700 - 307 cfm
Exhaust
0.100 - 51 cfm
0.200 - 107 cfm
0.300 - 154 cfm
0.400 - 186 cfm
0.500 - 210 cfm
0.600 - 223 cfm
0.700 - 229 cfm